How to order a new drive tray

I have a failed drive. I have the replacement drive. I can (easily) get the tray out of the R6. But I CANNOT remove the 4 screws that hold the failed drive to the tray. They won't budge. It's like they were tightened with a machine.

So I need to order a new tray. I'm NOT in warranty. I can't find a repair parts location or someone to call.